Synchronized motor clock movement



Feb. 24, 1942.

L. B. STONE 2,274,221

SYNGHRONIZED MOTOR CLOCK MOVEMENT Filed Oct. 3, 1939 2 Sheets-Sheet 1 BY I. 5+ L9 AV/3/ATTORNEY5 Feb. 24, 1942. STONE 2,274,221

SYNCHRONIZED MOTOR CLOCK MOVEMENT Filed Oct. 3, 1939 2 Sheets-Sheet 2 lNVENTOR ORNEY;

Patented Feb. 24, 1942 2,274,221

UNITED STATES PATENT OFFICE SYNCHRONIZED MOTOR CLOCK MOVEMENT Lucien B. Stone, South Orange, N. J assignor to Self Winding Clock Company, Inc., Brooklyn, N. Y., a corporation of New York Application October 3, 1939, Serial No. 297,649

4 Claims. (Cl. 58-34) My invention relates to synchronized motor disc l fixed on the hub of seconds arbor 9. The

clock movements and has the purpose of synsliding coupling is of a conventional type and is chronizing the clock movement by the motor powshown in detail in Fig. 6. It consists of a pawl er as soon as the distinct synchronizing impulse ll pivotally attached to disc III, the pawl being is received in the conventional manner. It is an :5. held in engagement with the aforementioned object of the invention to effect the synchroratchet wheel 8 by means of aspring l2. This nization by the motor power indirectly by means permits freedom of motion between the seconds of the power of a spring which is kept wound arbor 9 and the driving ratchet wheel 9 to a to a certain extent by the motor. A clock move- 7 limited extent, sufiicient friction being introduced ment in which the synchronizing action is per- 10' between the elements by means of the aforemenformed directly by the motor power is shown in tioned pawl II to normally drive the seconds my divisional application, Ser. No. 363,818, filed arbor from central arbor 6 while the clock runs November 1, 1940. in the normal way.

My invention is illustrated in the accompany- The minute arbor 28 is driven from central ing drawings, in which arbor 6 by means of the back gears l5, l6, ll, Fig. 1 is a front elevation of the clock movethe latter being a pinion which meshes with a ment in which the synchronizing power is supgear l8 loosely mounted on minute arbor 20. plied from the synchronous motor indirectly This gear is provided with a spring-controlled through a clock spring. pawl similar to the one illustrated in Fig. 6, which Fig.2 is aside elevation of Fig. l. pawl engages a ratchet wheel 22 fixed on a hub Fig. 3 is an enlarged sectional elevation of 23 which is in turn fixed on minute arbor 20. Fig. 1, substantially on line 3-3 of Fig. 1. Thus in a manner similar to that described with Fig. 4 is a section of a portion of Fig. 3 taken reference to the seconds arbor, the minute arbor substantially on line 4-4 of Fig.3. retains a restricted freedom of motion for ad- Fig. 5 is an enlarged section of Fig. 2% taken 25 justment purposes with respect to its drive, but substantially on line 55 of Fig. 2, some of the is normally driven by the aforementioned back elements unessential for the purpose of Fig. 5 gear from central arbor 6. The hour arbor is being omitted. not shown in the drawings. It is assumed to be Fig. 6 is a section of a portion of Fig. 3 taken mounted loosely in conventional manner on the on the line 66 of Fig.3. 30, minute arbor 20 and is driven from a pinion Fig. '7 is an enlarged section of a portion of 25 fixed on the minute arbor. This pinion meshes Fig. 2 taken substantially on line 1'I of Fig. 2, with the hour train and is indicated in Fig. 3

showing the stop arm in position to stop the only by the legend "To hour train.

synchronizing operation of the synchronizing For the purpose of synchronizing the minute m; and seconds arbors jointly when the conventional Fig. 8 is a section through the spring barrel hourly synchronizing impulse is received, a spring substantially on line 8-8 of Fi 3, and power motor is provided which is kept wound Fig. 9 is a section outside of the spring barrel to a limited extent by the synchronous motor taken on the line 9-9 of Fig. 3. and released to perform the synchronizing action Referring first to Figs. 1, 2 and 3, I and 2 rep- 0, in the following manner:

resent respectively the front and rear plates of On an arbor 32 journalled between the front the clock movement held apart by spacing rods and rear plates l and 2 is fixed a hub 34. This 3. Between these plates the clock trains are hub carries fixed to it a disc 35 provided near mounted in conventional manner. The power for its periphery with a stop pin 44 which appears driving the clock trains is supplied by the motor 451 in g. 3 only in dotted lines. On hub 34 is M mounted on the rear plate 2 of the movement loosely mounted the spring barrel 36 within and is shown only diagrammatically in Figs. 2 which the drive spring 31 is disposed. The inner and 3. The motor drives the normal clock trains end of this spring is fixed to hub 34, and the by means of a pinion 4 by way of a gear 5 which outer end, as shown in Fig. 8, is fixed to one of is fixed on the central drive arbor 6 on which the spacing pins 31a between the two spring the other tubular clock arbors are disposed. On barrel plates. The right-hand plate 36 in Fig. 3 central arbor 6 is fixed a hub I which carries is provided with ratchet teeth 38 which engage a ratchet drive wheel 8 for the purpose of driva retaining pawl 39 pivoted on an axle 39a mounting the seconds arbor sleeve 9 by way of a sliding ed between the two clock movement plates l and coupling, not shown in detail in Fig. 3, and a. 2. Retaining pawl 39 is more clearly shown in Fig. 8. It is assumed in Fig. 8 that the spring barrel is wound in the direction of the curved arrow in that figure, and retaining pawl 39, overbalancing on the left-hand end, engages the ratchet teeth 38 and prevents the spring barrel from rotating in the opposite direction but permits the barrel to rotate in the direction of the arrow.

On arbor 32 and adjacent to the spring barrel is loosely mounted a ratchet wheel 33 which is driven from central arbor 6 by way of gears 3| and 30. On the spring barrel, as shown in Figs. 8 and 9, is pivotally mounted at 4| a coupling pawl 46 so that it normally engages the ratchet wheel 33. The movement of pawl 43 away from ratchet wheel 33 is limited by a stop pin 42. The rear end 43 of pawl 40 is bent at right angles to the plane of the pawl and protrudes into the first turn of the drive spring 31, as shown in Fig. 8. This pawl end is for this purpose bifurcated, as shown in Fig. 8. Normally, when the spring is unwound, the position of the pawl is as shown in Fig. 9, in which its end 40 engages ratchet wheel 33. Thus a coupling is established between ratchet wheel 33 and the spring barrel through the pawl and thus by the running of the motor the spring is being wound. During the winding, the spring contracts and thus moves the rear end 43 of pawl 40 inwardly. After the spring has thus contracted and is wound to a certain extent, the rear end 43 of the pawl has been moved sufiiciently radially inwardly to disengage pawl 40 from ratchet wheel 33 and thus uncouples the spring barrel from the motor drive. In order to hold the inner end of spring 31 while the spring is wound, the aforementioned pin 44 on disc 35 is arrested in the following manner: The clock movement contains, for the purpose of exerting the synchronizing impulse, an impulse magnet 45 having an armature 46 pivoted in the clock casing at 41 in conventional manner. This armature carries an upwardly extending arm 48 which is shown in detail in Figs. and '7. Normally, that is to say, when no impulse is received, the armature 46 stands in the position shown in Fig. 5. Arm 48 is provided at its upper end with an inwardly extending nose 49 which carries at its upper portion a latch plate 52 which extends at right angles to the plane of lever 43 and directly into the path of the aforementioned pin 44 of disc 35. This pin is shown in dotted lines in Fig. 5. Thus, normally, that is to say, when the electromagnet 45 is not energized, pin 44 rests against the underside of latch plate 52 and thus prevents the disc 35 and in turn spring arbor 32 from rotating when the clock spring 31 is wound in the manner described. Nose 49 of spring release arm 48 further carries another latch 5| which is pivotally mounted at 50 (see Figs. 5 and '1) and normally rests under the influence of a curved spring 55 against a stop pin 54 provided on arm 48. This latch 5| carries a latch plate 53 similarly disposed to latch plate 52, that is to say, it extends toward disc 35 and into the path of pin 44. Assuming now that the spring is wound and an energizing impulse is received at magnet 45 and armature 46 is thereby attracted, arm 48 is pulled inwardly into the position shown in Fig. 7. This has two results. First of all, with latch 5| in its normal position shown in Fig. 5, the inward motion of arm 48 will permit pin 44 to slide off the right-hand end of latch plate 52, which thus releases pin 44 and allows the disc 35 to rotate in the direction of the arrow, Figs. 5 and 7, by the power delivered by the wound spring 31. However, as soon as pin 44 has come around again and approaches nose 49 of arm 48, this nose has been moved by the attraction of armature 46 sufliciently far inwardly to present the latch plate 53 into the path of pin 44. The latter throws latch 53 upwardly into the position shown in Fig. 7 in which it is held by virtue of the inclined edges 53a of the two latch plates which thus serve as a stop for the further upward movement of latch plate 53. This arrangement thus permits the resetting arbor 32 of the spring to perform only one revolution for each energizing impulse. As soon as the energizing impulse ceases, the armature 46 falls on and returns into the position shown in Fig. 5 in which arm 48 has moved sufiiciently far to the right to shift latch plate 52 over pin 44, thus retaining the pin in arrested position so long as the armature is deenergized. As soon as pin 44 is moved off latch plate 53, latch 5| is thrown downwardly again by spring 55 into the position shown in Fig. 5.

If the spring 31 becomes suihciently unwound to move the rear end 43 of pawl 40 in Figs. 8 and 9 outwardly, pawl 40 reengages driving ratchet wheel 33 which is being continually driven by the motor, and thus the rewinding of the clock commences until the spring is sufficiently wound to again disengage pawl 46 in the manner aforedescribed.

On spring arbor 32 are fixed two gears and 6|. Gear 60 meshes with a gear 62 loosely mounted on central arbor 6, and gear 6| meshes with a gear 63 loosely mounted on minute arbor 20. On central arbor 6 is also loosely mounted a resetting disc 64 which is frictionally coupled with gear 62 by means of a spring 66 in conventional manner. Likewise, on minute arbor 20 is loosely mounted a resetting disc which is frictionally coupled with gear 63 by a conventional coupling spring 61. On disc 64, as shown more clearly in Fig. 4, is pivoted at 16 a resetting pawl 68 which is curved as shown in Fig. 4 so that it can engage a pin 69 fixed on the aioredescribed disc l0 fixed on the seconds arbor 9. Pawl 68 is held in the position shown against a stop pin 1| by means of a spring 12. This pawl is provided with a slightly inwardly curved tail 13 which extends sufiiciently rearwardly at its outer end so as to permit normally, that is to say, when disc 64 is standing still, pin 69 of the minute arbor to ride onto this tail when the pin revolves in the direction of the arrow, Fig. 4. Thereby pawl 68 is tilted inwardly and permits pin 69 to pass. With the assumption that normally the resetting mechanism including the spring 31 and the two driving gears 60, 6|, and gears 62 and 63, and discs 64 and 65, stands still, the seconds arbor is free to be rotated in the normal clockwise direction by the motor M, and every time pin 69 passes pawl 68 the latter is tilted back and allows the pin to pass. A similar arrangement is provided for the minute arbor, namely, the aforementioned resetting disc 65 is provided with a resetting pawl 19, shown in detail in Fig. 5, and constructed similar to pawl 58 shown in Fig. 4. It is provided with a tail 8| which permits pin 15 of disc 24 attached to ratchet wheel 22 (see Fig. 3) to pass when the pin rotates in the normal clockwise direction during the operation of the minute arbor.

Armature 46 is provided with two further arms 16 and 11. In the sectional elevation, Fig. 5, only arm 11 is shown. This is the arm for controlling the resetting of the minute arbor, The other arm 16 which controls the resetting of the seconds arbor, is directly behind arm 11 in Fig. 5..

The operation of both arms is alike and occurs simultaneously so that only the operation of arm 11 with respect to the minute setting will be described with reference to 'Fig. 5, Arm 1'! is provided with a nose 18 extending toward central arbor 6 and bevelled as shown at 19 at its outer end. When armature 43 is attracted, nose I8 is moved inwardly in the direction of the arrow into the path of pin "i of disc 24 aforementioned.

The operation of the mechanism is as follows: Let us assume that the resetting spring 31 has been wound by the motor and that the spring drive is locked by pin 44 and latch 52 in Fig. 5 in the manner aforedescribed. Let us further assume that the position of the upper edge 18a of nose 18, in case the armature is attracted, represents a zero or full hour position of the minute hand. Let us further assume that the clock is say 5 minutes slow, which may be indicated in Fig. 5 by the position of pin with relation to the upper edge 18a of nose 18 when the armature is attracted. Now, as soon as the synchronizing impulse is received at electromagnet 45 at the full hour, armature 46 is attracted thereby and arms 48, T6 and TI are moved inwardly. The inward movement of arm 48 as aforedescribed temporarily releases pin 44, and

thereby permits the resetting spring 31 to drive the disc one revolution, after which it is locked again in the manner shown in Fig. 7, as aforedescribed. At the same time, arms 16 and 11 have moved inwardly and, for instance, arm

H has moved its nose [8 and its surface 18a into the path of pin 75. The release of the spring power at the reception of the impulse and the rotation of disc 35 rotates spring arbor 32 and thus rotates disc 65 with its resetting pawl I9. The latter engages with its curved portion 80, pin 75 which is in its path and picks up this pin and moves it forward in the direction of the arrow, that is to say, in the normal clockwise direction. Edge 18a of nose 18 standing in the path of the pin, the latter is stopped by this edge and the resetting motion is completed. If it should happen that pin 15 is stopped before pin 44 of spring motor 31 is arrested, 1. e. before it has made its complete revolution, the coupling spring 61 permits the spring drive to continue until pin 44 is stopped. This coupling spring arrangement for the minute as well as for the seconds arbor is also of advantage in case the two arbors fail to reach the synchronized position simultaneously. In that case the arbor which is behind can still be moved ahead to its stop position by the resetting train, while the other arbor, due to its spring coupling, allows the resetting drive to slide. It is understood of course that the rotation of disc 35 and spring arbor 32 is quite fast so that pin 15 and thus the minute arbor 20 is thrown quickly into the correct full hour position, practically at the moment when electromagnet is energized. The same occurs with respect to the seconds arbor, the pin 69 of which is picked up by the resetting pawl 68 (see Fig. 3) and thrown against the appertaining armature arm 16 so that also the seconds arbor is thereby reset in case it should not be on time.

This resetting arrangement so far operates only in case the clock is slow. In most of the synchronous motor drives, the clocks if out of time are slow and not fast, and the arrangement is made in such manner that the full revolution of the resetting spring arbor 32, as described hereinbefore, suflices to synchronize a clock which is as much as fifty minutes slow. It may happen, however, that the clock is fast. This amounts generally at most to not more than a few minutes. In order to reset the clock movement described when it is slightly fast, the noses of arms it and H are bevelled at their outer ends as shownin Fig. 5 at 19 with respect to the nose of arm l1. If the clock should be fast, pin 15 would in that case stand slightly below the zero position, which is marked by 0 in Fig. 5, so that when the resetting impulse is received at the electromagnet 45, the inclined end 19 of nose (8 will pick up pin 3'5 and push it upwardly counterclockwise into the zero position. This occurs in similar manner with respect to the seconds arbor. After the synchronizing impulse ceases, arms 11, I6 and 48 fall ofi and the pin 44 of the resetting mechanism slides onto latch plate 52 of arm 48 and thus the resetting spring drive is again locked.

While I have shown and described a particular form of spring power device for accumulating a certain amount of energy delivered by the motor in the course of its normal operation for the purpose of releasing this accumulated power during the resetting period, it is obvious that other spring power devices well known in the art may be substituted.

I claim:

1. In a clock mechanism, a hand arbor, a motor, a clock train connecting said hand arbor with said motor and including a slip friction coupling, an element connected to said hand arbor, a resetting member having a driving movement and disposed to engage said element in the course of its driving movement to impart a continuous movement thereto sufiicient to rotate said hand arbor from any angular position to a predetermined synchronizing position, springoperated driving means for said resetting member, arresting means normally restraining said driving means, means driven by said motor to wind the spring of said driving means, means adapted to respond to a synchronizing impulse to operate said arresting means to release said driving means, and stop means including a positioning element connected to said hand arbor and an abutment member movable simultaneously with said impulse responsive means into the path of said positioning element.

2. In a mechanism for synchronizing motor driven clocks by the driving motor power, a clock train and means for continuously driving said train from the motor, a resetting gear train geared to move said clock train at a speed higher than its normal speed for advancing the clock hands when slow, a spring power accumulator disposed to operate said resetting train and means connected with said driving motor for storing a limited amount of energy in said accumulator during the normal operation of said motor, means for arresting the operation of said accumulator during the normal operation of the clock, means for delivering a synchronizing impulse at the desired time intervals, mean controlled by said impulse for releasing said accumulator to operate said resetting train and for re-arresting said accumulator after the completion of the resetting operation, a pawl connected with said resetting train and disposed to engage the clock train during the forward motion of the resetting train, but to permit normally free operation of the clock train when the resetting train is not in operation, whereby the clock train if slow is advanced by the resetting train, and means controlled by said synchronizing impulse for arresting the clock train in its advance for the duration of the impulse when the clock train has arrived at the required time position.

3. In a mechanism for synchronizing motor driven clocks by the driving motor power, a clock train and means for continuously driving said train from the motor, a resetting gear train geared to move said clock train at a speed higher than its normal speed for advancing the clock hands when slow, a spring power accumulator disposed to operate said resetting train and means connected with said driving motor for storing a limited amount of energy in said accumulator during the normal operation of said motor, mean for arresting the operation of said accumulator during the normal operation of the clock, means for delivering a synchronizing im- 2 while the resetting train is not in operation to permit normally free operation of the clock train,

whereby the clock train if slow is advanced by the resetting train, and a stop arm controlled by said synchronizing impulse for arresting the clock train in its advance for the duration of the impulse when the clock train has arrived at the required time position.

4. In a mechanism for synchronizing motor driven clocks by the driving motor power, a clock train and means for continuously driving said train from the motor, a resetting train disposed to advance the clock train when slow and a spring power accumulator for driving said resetting train, means connected with said driving motor for storing a limited amount of energy in said accumulator during the normal operation of said motor, a latch pin on said accumulator and a locking arm having a latch plate disposed in the path of said pin for normally locking said accumulator in energy storing position, means connected with said arm for producing a synchronizing impulse at the desired time intervals whereby said arm is actuated to move said latch plate off said pin to permit the operation of said accumulator, and a second latch plate on said arm movably disposed in the path of said latch pin when said arm is in actuated position to catch said pin and arrest the accumulator after one revolution in position for the pin to be locked by said first latch plate when said arm returns to normal position after cessation of the impulse.

LUCIEN B. STONE. 

